have_chap_secret
have_chap_secret(user, (explicit_remote? remote_name: NULL), 0, NULL);
havesecret = have_chap_secret((explicit_remote? remote_name: NULL),
static int have_chap_secret __P((char *, char *, int, int *));
can_auth = have_chap_secret((explicit_remote? remote_name: NULL),